Cutter-bar



LOUIS N. HATHAWAY, MOSES W. TVVOMBLY, AND ELMER I-I. HAMITIIOND, OFLAOONIA,

NEW HAMPSHIRE.

CUTTER-BAR.

Application filed May 8,

To all whom it may camera:

Be it known that we, LoUIs N. HATHA- \VAY, Mosns V. TwoMBLY, and Emma H.HAMMOND, citizens of the United States of America, and residents ofLaconia, in the county of Belknap and State of New Ha1npshire, haveinvented new and useful Improvements in Cutter-Bars, of which thefollowin is a specification.

Our invention relates to the construction of cutter bars for mowing,reaping, and similar agricultural machines, and has for its objects theprovision of improved means for detachably securing cutter blade sections to the bar or back strip which carries them, for securelyretaining said blade sections on the back strip, and for readily andeasily removing and replacing such cutter blade sections whenever .thisis required.

It is not infrequently necessary to remove and replace cutter bladesections while the machine'is at work in the field; our improvements areintended and adapted to facilitate such operations, to reduce theincidental mechanical operations to a minimum and to prevent accidentalloss of machine parts.

In the drawings hereto annexed, which illustrate our invention andexhibit it in the form believed by us to be the best,

Figure 1 shows, in top plan view, partly broken away, a portion of acutter bar;

Fig. 2 shows the same in rear elevation;

Fig. 3 is a cross section taken at the line of Fig. 1, and shows alsosundry associated machine parts which are omitted from Fig. l; and

Fig. 4 is a perspective view of one of the blade-holding bolts.

The mechanical environment to which our improvements are adapted is tobe found in any mowing or reaping machine which employs a reciprocatingcutter bar,'comprising a series of blade sections mounted on a backstrip which is fitted to slide in a framebar, and is reciprocated byappropriate mechanical connections with the running gear of the machine.The cutter blade sections are of the usual shape, and are designated inthe-- drawings by the numeral 1. These are mounted on the reciprocatingback-strip 2, which slides in front of the frame bar 12. Bladeretainingfingers or plates 13, and guards 14, are such as are usually employed.

The cutter blade sections 1 are arranged Specification of LettersPatent.

Patented July 29, 1920.

1920. Serial No. 379,794.

in series, and in marginal contact with each other, along the back stripEach blade section is marginally recessed at =9, so that the recesses ofadjacent blade sections-register with each other and provide abolt-hole, in which the cylindrical shank of a bolt 3 fits closely, sothat the cutter blade sections contour departs from a surface ofrotation (such as a cylindrical surface) so that a bolt, conformed tofit the bolt hole will not be able to rotate in the hole. In thisrespect the bolt holes are functionally equivalent to squared boltholes, which also depart in contour from a surface of rotation. But inorder to deplete the structural strength of the back strip 2 as littleas possible, the recesses S are disposed longitudinally of the backstrip, thus leaving as much metal as possible in cross section betweenthe bolt hole and the edges of the back strip.

The holding bolts 3 have the usual-screw threaded shanks, but areprovided with lugs or projections 1010, adjacent to the bolt head 11,which, when a bolt is inserted in a hole 7 in the back strip, are lodgedin the recesses 8, and securely retain the bolt against any tendency toback ofif.

The holding-down nuts 4, which are threaded to takethe bolts 3, areelongated, and sufiiciently resilient to yield at their ends and rideover projections 5, 5, which rise above the surface of eachblade-section 2. These projections, of which there are two on each bladesection may conveniently be formed by means of a die which, indentingthe lower surface of the blade-section forces out the projection on theupper surface. The projections are so located on the blade sections thatwhen a nut 4 is screwed home and forced over the two projections (one onone blade section, the other on an adjoining blade-section) the nut lieswith its long axis about parallel with the back strip 2. When thussecured, the nut 4 is prevented from backing off by the projections 5,which however, being rounded, as indicated by the shading in Fig. l asshown in elevation in Fig. 2, have such shape that when it is desired toloosen the nut, the ends of the nut will spring upward and ride over theprojections. An ordinary wrench will serve to manipulate the nut 4either for setting or loosening.

To remove a blade section and replace it} with another, all that isnecessary is to remove the nut 4 from one of the bolts 3 which engageand hold the blade-section, and to loosen the similar nut from the otherholding-bolt. The blade can then be lifted out, and another oneinserted. The only pieces which have to be detached in order to take outa blade are the bolt 3 and nut 4t which were selected for removal. Asthis nut and bolt will naturally be removed by the lingers of theworkman-having been released from theirtight hold by a wrenchtheliability of their being mislaid or lost is very small.

It will be apparent that the back strip 2 does not have to be disturbed,and that the entire repair-ope'ation can be easily performed in thefield, with very little :loss of time. I

jections on the blade-sectionsto engage said nuts. 7

2. In a cutter bar, the combination of a series of cutter blades havinmutually registering marginal recesses to form bolt-holes, a back stripon which the blade sections are carried provided with recessed boltholes,

1. In a cutter bar, the combination of bolts having lateral extensionsto engage the recessed bolt holes, passing through the back strip andsaid bolt-holes, elongated'nuts', and projections on the blade sectionsto engage said nuts. 7 ,7 V

3'. In a cutter bar, the combination of a series of cutter blades,having mutually registering marginal recesses to-to'rm bolt-holes,

' a back strip on which the blade sections are carried, provided withbolt holes recessed longitudinally of the back strip, bolts 'havinglateral extensions to engage the recessed boltholes, passing through theback strip and said bolt holes, elongated nuts, and projections on theblade sections to engage said nuts. s v

.4. In a cutter bar, the combination of a series of cutter blades havingmutually registering marginal recesses to form bolt holes, a back stripon which theblade-sectionsare carried,bolts passing through the backstrip and said bolt-holes, resilient nuts, and projections on the bladesections to engage said nuts. r

5. Ina cutterrbar, thercombinationota V series of cutter blades havingmut'ually registerlng marginal recesses to form bolt holes, aback stripon which the blade-sections are carried, bolts passing through the backstrip and said bolt-holes, resilient elongated nuts,

and projections on the blade sections to en-.

gage said nuts. I 1

Signed by us at Laconia, New Hampshire, this sixth day May, 1920.

LOUIS N. HATHAWAY. MOSES w. TWOMBLY; 1 .ELMER 1-1. HAMMOND.

